变压器的瓦斯保护和差动保护能否相互代替?

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问题:

变压器的瓦斯保护和差动保护能否相互代替?

考点:热力发电厂机炉电考试蒸汽机测点及继电保护蒸汽机测点及继电保护题库
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己知二次函数y=f(x) 的图象过点(1,-4),且不等式f(x)<0的解集是(O,5).

(I )求函数f(x)的解析式;

(II)设g(x)=x3-(4k-10)x+5,若函数h(x)=2f(x)+g(x)在[-4,-2]上单调递增,在[-2,0]上单调递减,求y=h(x)在[-3,1]上的最大值和最小值..

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短文改错 。
     此题要求改正所给短文中的错误。对标有题号的每一行做出判断:
     如有错误(每行只有一个错误),则按下列情况改正:
     1. 该行多一个词:把多余的词用斜线(\)划掉,在该行右边横线上写出该词,并也用
斜线划掉。
     2. 该行缺一个词:在缺词处加一个漏字符号(^),在该行右边的横线上写出该加的词。
     3. 该行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词。
Anita Mei was very famous pop singer in Hong Kong. Together
with her mother, she began to perform in the age of four. In the
early 1980s, she took part in a local sing competition and won the
first prize. The song "Bad Girl" made him famous. The following
years saw Anita make many records. Some of her song were very
popular. She was always ready to help others, but she made a lot
of good friends. When SARS hits Hong Kong, she organized
several concerts with other pop stars call on Hong Kong people
to brave face the disease. Sadly, Anita died of cancer in 2003. The
brave or beautiful lady will always be remembered by people.
1. _____
2. _____
3. _____
4. _____
5. _____
6. _____
7. _____
8. _____
9. _____
10. _____
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图甲为某科考队于当地时间2010年2月28日10时30分在斯瓦尔巴群岛考察时拍摄的照片,图乙为拍摄地点位置图。读图回答1~2题。

 

图甲                                            图乙

1.图甲景观可能反映[ ]

A.全球气候变冷

B.生物种群繁多    

C.北极冰盖退缩    

D.海洋环境污染

2.此照片拍摄时,北京时间为[ ]

A.3月1日17时30分            

B.2月29日17时30分          

C.2月28日17时30分          

D.2月28日3时30分

题型:问答题 简答题

将实验和对照在同一受试对象身上进行的对照称为

A.空白对照
B.实验对照
C.标准对照
D.自身对照
E.相互对照

题型:问答题 简答题

给矿作业对浮选指标有何影响?

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